Optische afstandmeter (Sokhisha). IK 5-206 Instruments de photogrammétrie / Societe d'optique et de mecanique de haute precision (SOM) Marconi instruments 1954 : a cataloque of the telecommunication measurement equipment and industrial electronic instruments / Marconi Instruments pamphlet Directions for the use of artillery instruments : Sound ranging equipment, miscellaneous Handbook of artillery instruments and range-finders : Range-finders nos., 2, 11, 11a, 13 & 13a / The War Office. Part 1 / The @War Office Handleiding voor de veldartillerie. Instrument. 5 grafieken en nomogrammen. nr. 1735 t.d. publ instrumenten van het bomvliegtuig B 25 / samengesteld door de Militaire Luchtvaart. Vliegtechnische Dienst Directions for the use of anti-aircraft artillery instruments. Pamphlets Instrument flying techniques and procedures, January 1951 Instrument flying techniques and procedures, October 1953 Theory of instrument flying tm Instrument lights M19, M31, M34, M35, M37, M38, M47, 6578454 and 7983714, 1955